Creating multiline strings in JavaScript (the problem of string wrapping in JS)

Q

I have the following code in Ruby. I want to convert this code into JavaScript. what’s the equivalent code in JS?

text = <<"HERE"
This
Is
A
Multiline
String
HERE

A-1

ECMAScript 6 (ES6) introduces a new type of literal, namely template literals. They have many features, variable interpolation among others, but most importantly for this question, they can be multiline.

ECMAScript 6 (ES6) introduced a new type of text, namely 模板文字. They have many functions, including variable interpolation, but the most important thing for this problem is that they can be multi-line.

A template literal is delimited by backticks:

Template text is separated by backticks:

var html = `
  <div>
    <span>Some HTML here</span>
  </div>
`;

(Note: I’m not advocating to use HTML in strings)

(Note: I do not advocate using HTML in strings)

A-2

As the first answer mentions, with ES6/Babel, you can now create multi-line strings simply by using backticks:

As mentioned in the first answer, with ES6/Babel, you can now create multi-line strings just by using backticks:

const htmlString = `Say hello to 
multi-line
strings!`;

Interpolating variables is a popular new feature that comes with back-tick delimited strings:

Interpolation variables are a popular new feature, with strings separated by backticks:

const htmlString = `${
      
      user.name} liked your post about strings`;

This just transpiles down to concatenation:

This is just converted to concatenation:

user.name + ' liked your post about strings'

Original ES5 answer:

ES5 original answer:

Google’s JavaScript style guide recommends to use string concatenation instead of escaping newlines:

Google的JavaScript样式指南It is recommended to use string concatenation instead of newline:

Do not do this:

Do not do this:

var myString = 'A rather long string of English text, an error message \
                actually that just keeps going and going -- an error \
                message to make the Energizer bunny blush (right through \
                those Schwarzenegger shades)! Where was I? Oh yes, \
                you\'ve got an error and all the extraneous whitespace is \
                just gravy.  Have a nice day.';

The whitespace at the beginning of each line can’t be safely stripped at compile time; whitespace after the slash will result in tricky errors; and while most script engines support this, it is not part of ECMAScript.

The whitespace at the beginning of each line cannot be safely stripped at compile time; spaces after the slash will cause tricky errors; although most script engines support this feature, it is not part of ECMAScript.

Use string concatenation instead:

Please use string concatenation:

var myString = 'A rather long string of English text, an error message ' +
               'actually that just keeps going and going -- an error ' +
               'message to make the Energizer bunny blush (right through ' +
               'those Schwarzenegger shades)! Where was I? Oh yes, ' +
               'you\'ve got an error and all the extraneous whitespace is ' +
               'just gravy.  Have a nice day.';

A-3

the pattern text = <<"HERE" This Is A Multiline String HERE is not available in js (I remember using it much in my good old Perl days).

This mode text = <<"HERE" This Is A Multiline String HEREis not available in js (I remember I used it a lot during my good time in Perl).

To keep oversight with complex or long multiline strings I sometimes use an array pattern:

In order to supervise complex or long multi-line strings, the array mode is sometimes used:

var myString = 
   ['<div id="someId">',
    'some content<br />',
    '<a href="#someRef">someRefTxt</a>',
    '</div>'
   ].join('\n');

or the pattern anonymous already showed (escape newline), which can be an ugly block in your code:

Or the anonymous mode (newline character) that has been shown, which may be an ugly block in the code:

 var myString = 
       '<div id="someId"> \
some content<br /> \
<a href="#someRef">someRefTxt</a> \
</div>';

Here’s another weird but working 'trick’1:

This is another weird but effective "trick" 1:

var myString = (function () {
    
    /*
   <div id="someId">
     some content<br />
     <a href="#someRef">someRefTxt</a>
    </div>        
*/}).toString().match(/[^]*\/\*([^]*)\*\/\}$/)[1];

ES20xx supports spanning strings over multiple lines using template strings:

ES20xx supports the use of 模板字符串spanning multiple lines 字符串:

let str = `This is a text
    with multiple lines.
    Escapes are interpreted,
    \n is a newline.`;
let str = String.raw`This is a text
    with multiple lines.
    Escapes are not interpreted,
    \n is not a newline.`;

1 Note: this will be lost after minifying/obfuscating your code

1 Note: After minifying/obfuscating the code, this will be lost

A-4

141

I came up with this very jimmy rigged method of a multi lined string. Since converting a function into a string also returns any comments inside the function you can use the comments as your string using a multilined comment /**/. You just have to trim off the ends and you have your string.

I came up with this very clumsy manipulation of multi-line strings. Since converting a function to a string will also return any comments inside the function, you can use multi-line comments / ** / to use comments as a string. You only need to trim the ends.

var myString = function(){
    
    /*
    This is some
    awesome multi-lined
    string using a comment 
    inside a function 
    returned as a string.
    Enjoy the jimmy rigged code.
*/}.toString().slice(14,-3)

alert(myString)